ZID ARTCC radar controller lost separation between a cruise and descending aircraft.

Attributes
ACN	580235
Time
Date	200304
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : pxv.vortac
State Reference	IN
Altitude	msl single value : 37000
Environment
Flight Conditions	Mixed
Weather Elements	Turbulence
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zid.artcc
Operator	common carrier : air carrier
Make Model Name	A319
Operating Under FAR Part	Part 121
Navigation In Use	other vortac
Flight Phase	cruise : enroute altitude change
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zid.artcc
Operator	common carrier : air carrier
Make Model Name	EMB ERJ 145 ER&LR
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	flight time total : 210
ASRS Report	580235
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation non adherence : published procedure
Independent Detector	atc equipment : conflict alert other controllera
Resolutory Action	none taken : insufficient time
Consequence	faa : investigated
Miss Distance	horizontal : 20400 vertical : 600
Supplementary
Problem Areas	ATC Human Performance
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

Volume and complexity at sector were increasing. Corrective action was taken before captain activated.

Original NASA ASRS Text

Title: ZID ARTCC RADAR CTLR LOST SEPARATION BTWN A CRUISE AND DSNDING ACFT.

Narrative: VOLUME AND COMPLEXITY AT SECTOR WERE INCREASING. CORRECTIVE ACTION WAS TAKEN BEFORE CAPT ACTIVATED.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.